Firefighters at the scene of a major incident are faced with the loss of both hearing and vision. Dense smoke can reduce visibility to inches, and ambient noise levels from a major fire can reach 85 decibels. Infrared cameras can help in search and rescue operations by providing information that can be used in identifying a building's structural elements such as exits. Information from the infrared cameras can further assist in locating firefighters lost in the building. However, identifying other structural elements such as hallways and stairways in a building remains largely a best guess endeavor, which can only be supplemented by feeling through debris and damaged structures.